The document discusses enterprise architecture (EA), its definitions, motivations, and frameworks, highlighting its role in addressing organizational complexity and alignment with business strategies. It outlines the historical evolution of EA and details various methodologies, modeling techniques, and tools used in the field, along with research conducted by the Alqualsadi team led by Karim Baïna. The document emphasizes the importance of governance, quality, and integration in EA, and lists research outputs and collaborations within the academic community.

1. www.ensias.ma www.um5s.ac.ma
Alqualsadi research team
on Enterprise Architecture
Prof/A. Karim Baïna
baina@ensias.ma
www.ensias.ma/ens/baina
http://ma.linkedin.com/in/karimbaina
April, 16th 2010

2. According to some prealable unformal
questionnaire – you want to know
What is EA ? What are EA concepts ?
What is EA for ?
Is it not yet another buzzword ?
Is it not yet another marketing artefact to sale
licences, books, trainnings, and consulting ?
Is it really with an added value ? Within the
modelling life cycle ? If yes how to position it ?
How to compare EA with other modelling
methods and frameworks ?

3. Outline
1. Enterprise Architecture
2. Alqualsadi EA research team
3. Karim Baïna’s current research interest
4. A historical/cultural parenthesis
5. Open discussion

4. www.ensias.ma www.um5s.ac.ma
Enterprise
Architecture

5. Motivation behind EA
EA has been firstly thought to address two problems (in 1987) :
System complexity : organisations were spending enormous
budgets in IT
Poor business alignement : organisations were finding it more
difficult to keep IT systems alignes with business model
Basically enterprise are looking for more agility, high profils,
lower risk, more satisfied senior management, and
More cost and less value problem recognised 23 years ago, but
have today reached a crisis point.
Roger Sessions, CTO of ObjectWatch©

6. Kind of real problems EA is
supposed to answer to
Jeanne Ross 2005 ©

7. Peter Weil 2007 ©

8. Enterprise Architecture – definition 1
for A. Goel et al., EA is a
holistic expression (of the enterprise)
in terms ofkey strategies usually evolving from different domains of(i)
business architecture (business strategy, processes, services,
structure, policies and governance), (ii) information architecture
(ontologies, taxonomies, meta-data, master data, transaction data,
information flows and other forms of data and information assets related
to the enterprise), and (iii) technology architecture (infrastructure,
security, applications, technology services and middleware), 2009.
With regards to
enterprise
Functions, Data,
Roles & Units,
Expression Events,
EA EA Ressources,
Produits & services,
etc.
EA
K. Baïna & S. Slimani 2010 ©

9. Enterprise Architecture – definition 1
M. Lankhorst defines EA as
a coherent whole of principles, methods, & models
that are used in the design & realization of an enterprise’s
(i) organizational structure, (ii) business processes, (iii)
information systems, and (iv) infrastructure, 2005.
Method
s
Principl
s
Realisation
K. Baïna & S. Slimani 2010 ©

10. Enterprise Architecture – definition 3
For Gartner Group, EA is the strategic planning process that
translates(an enterprise's business vision & strategy)
into effective enterprise change, 2010.
EA EA
EA as strategic planning process
K. Baïna & S. Slimani 2010 ©

11. Enterprise Architecture
EA
EA
Expression
EA EA
EA as strategic planning process
Met
hod
s
Prin
cipls
Realisation
OSmodel BPmodel ISmodel Inframodel
K. Baïna & S. Slimani 2010 ©

12. EAF Concepts, Principles and
methodology
EA dimensions
Concepts :
Enterprise views or perspectives : function (activity),
information, resource, organisation unit, role, behaviour
(business process), etc.
modelling constructs (ie documents, and reports, aka
artefacts)
flows : Materials, Information and Control
Principles
Separating enterprise behaviours from functions
Separating enterprise behaviours from resources
Separating enterprise resources from roles & organisation
units
Structured methodology
Models
Tools

13. EAF - Enterprise Architecture
Frameworks
An EAF is proposal of a reference architecture
or structure for Enterprise Architecture (like an
Enterprise Architect toolkit)
Main EAFs
1. Zachman Framework (Zachman Institute of
Architecture)
2. TOGAF (The Open Group Architecture Framwork)
3. FEA (Federal Enterprise Architecture, US White
House)
Many other EAFs
1. US Government Frameworks (DoDAF (US Department of
Defence), MoDAF (UK Ministry of Defence), TEAF (US
Department of Commerce), CEAF (US White House), EA Cube
(Scott Bernard), CIMOSA, GERAM (ISO 15704 2000), GRAI,
PERA, RM-ODP (ISO/IEC 10746), etc.

14. EA Timeline: genesis and
evolution
age date event
0 1987 Zachman's first article
1993 Customer members demand archtecture standards…
1994 TAFIM Released
8 1995 TOGAF first published
1996 Clinger/Cohen Bill passed
1998 TAFIM Retired
1999 FEAF 1.2 Released
2001 TOGAF 7 - Technical edition
15 2002 FEA replaces FEAF
2002 TOGAF 8.0 "Enterprise" released
2003 TOGAF 8.1 (first certification program launched)
2005 Gartner/Meta merger
19 2006 FEA mostly complete
2006 TOGAF 8.1.1
22 2009 TOGAF 9.0 final draft approval
2010 now

15. EA methodologies and modelling
techniques – some examples
EA methodologies
TOGAF ADM (Architecture Development Method)
All US Government Frameworks include a methodology sepecific to their
EAF (DODAF, FEAF, TEAF)
Gartner/Meta Methodoly
EAP
EA Cube Method
SEAM
EA modeling techniques and notations
Archi-Mate, UEML, SysML, BPMN, ERD and IDEF, etc.
EA modeling tools
ARIS Process, IDS Scheer
MEGA
Abacus, Avolution
Enterprise Architect, Sparx
System Architect, IBM Telelogic
BizzDesigner, Bizzdesign
Altova Enterprise, Altova

16. Zachman Framework
(used for its structured architecture artefacts taxonomy – Zachman grid)
DATA what FUNCT.how NETWK. where PEOPLE who TIME when MOTIV. why
Scope
contextual
Planner view
Business
Model
conceptual
Owner view
System
Model
logical
Designer view
Technology
Model
Physical
Builder view
Detailed
Representations
Out-Of-Context
Sub-Constractor
view
Functionning
enterprise
User view

17. TOGAF (used mainly for its ADM method)
For TOGAF, divides an architecture into 4
categories :

18. TOGAF ADM (Architecture
Development Method)

19. TOGAF ADM (Architecture
Development Method)

20. FEA (use mainly because of its most complete framework)
Complies with the Clinger-Cohen Act
Provides a common methodology for IT acquisition

21. Benchmark of 4 and main EAFs
Data is from Roger Sessions
Not the data-based synthesis diagram view

22. Focus Area for EA
Infosys 2007 ©

23. Adopted Industry Standard
Frameworks
Infosys 2007 ©

24. EA Tool used
Infosys 2007 ©

25. EA delivrables

26. EA and IT Governance

27. EA & Alignment –
EA
Alignement
life Cycle
Paul Harmon 2003 ©

28. EA modelling tools – Gartner
Quadrant

29. www.ensias.ma
Alqualsadi
www.um5s.ac.ma
Enterprise Architecture
research team

30. Alqualsadi team - Research axes
Entreprise Architectures, Quality of their
Developement and Integration
Axe 1 : EA Governance Axe 2 : EA Integration Axe 3 : EA Quality
Enterprise Architecture
Axe 5 : Applied Maths Methods for EA Axe 4 : EA Applied to ICT4D

31. Alqualsadi team - Research axes
Entreprise Architectures, Quality of their
Developement and Integration
Axe 1 : EA Governance Axe 2 : EA Integration Axe 3 : EA Quality
KPI/GKI/KFS models for IT Strategy, Portal/Process/Service/Component MDE/MDA, EA models formal
Governance, Maturity & Alignment. User-centric syntactic/semantic/technical specification and validation.
TOGAF/DoDAF,COBIT, CMMi. integration and interoperability. B methods, Graphs, PN, LTL/TTL,
through SOA/BPM/MDM/ERP/Portals/3G. but also Six sigma, ITIL.
Enterprise Architecture
Axe 5 : Applied Maths Methods for EA Axe 4 : EA Applied to ICT4D
statistics and quantitative method for EA quality, optimal e-Gov,e-health, and e-education.
control for IT alignment, modelling for ITG, Citizen-centric approach for EA use.

32. Alqualsadi statistics
Age : 4 years
Scientific Production
3 books
16 journal papers
26 national conference papers
45 international conference papers
1 Habilitation (Docent/Docentu)
5 defended Phs Thesis
14 defended Master by research
32

33. Alqualsadi Team permanent members,
and their main research axes
6 researcher-professors :
2 Profs.
Mme Laïla Kjiri : EA Quality, Maths Methods, and Governance
Mr. Bouchaïb Bounabat : EA in ICT4D (mainly in e-gov), and
Governance
2 Prof/Assoc.
Mr. Karim Baïna : EA Quality, Integration, Governance, and Maths
Methods, (leader of Alqualsadi)
Mr. Saïd Achachab : EA App. Maths Methods for EA, and
Governance
2 Prof/Assist.
Mme Mounia Fredj (*): EA Integration, and Quality
Mr. Salah Baïna : EA Governance, Quality, and Maths Methods.
To contact members : {<name>@ensias.ma, except for <sbaina>}
18 PhD in progress (14 females, and 5 males) 78% of females
Many Masters by research (in progress)
(*) (Nielsen Danish family line)

34. Alqualsadi Team non-permanent
members, and their main research axes
6 researcher-professors :
1 Prof.
Mr. Hassan Abdelwahed, Semlalia Sciences Faculty, Cadi Ayyad
University, Marrakech : EA Integration, and ontologies based web
2.0 Portal Integration
1 Prof/Assoc.
Mme Salma Mouline, Sciences Faculty of Rabat, Mohammed V –
Agdal University, Rabat : EA Quality and Integration
1 Prof/Assist.
Mr. Mohammed Berrada, ENSAF, USMBA, Sidi Mohamed Ben
Abdellah University, Fès : EA organisational perspective
modelling and verification
1 Dr., and chairman of EA governance startup company
Mr. Tawfik Es-squalli, NEOXIA MAROC, Casablanca
(member of The Open Group) : EA Governance mode,
and Quality of their development and integration

35. Partnerships
National partners :
EMI, Ecole Mohammedia des Ingénieurs
Sciences Faculty of Rabat, Mohammed V – Agdal University, Rabat
NEOXIA MAROC, Casablanca (member of The Open Group)
International partners :
France
Prof. Claude Godart, ESSTIN, Nancy University, LORIA, Nancy
Prof. Hervé Panetto , CRAN, Nancy
Prof. Djamel Benslimane, LIRIS, Lyon
Prof. Kamel Barkaoui, CNAM, Paris
Prof. Assoc. Samir Tata, INT, Paris
Prof. Jean-Pierre Giraudin, IMAG, Grenoble
Sweden
Prof. Paul Johannesson, Dr. Petia Wohed, DSV, Stockholm University,
Stockholm
Belgium
Prof. Michael Petit, UNDP, Namur
United Kingdom
Prof. Zied Ouertani, University Of Cambridge, Cambridge

36. Some journal publications of
Alqualsadi team :
2010
M.Z. Ouertani, S. Baïna, L. Gzara and G.Morel. Traceability and management of dispersed product
knowledge during design and manufacturing 2010 Journal of Computer-Aided Design, Special Issue on
Product Lifecycle and Knowledge Management. (JCAD’2010)
2009
S. Baïna, Panetto, Morel. New paradigms for a product oriented modelling: Case study for traceability 2009
Computers In Industry’2009 60 3 172-183
S. Baïna, H. Panetto, K. Benali. Product Oriented Modelling and Interoperability Issues 2008, Lecture Notes
in Business Information Processing (LNBIP’2009) 3 293-308
2008
W. Gaaloul, K. Baïna, and C. Godart. Log-based Mining Techniques Applied to Web Service Composition
Reengineering 2008 (SOCA’2008), Service Oriented Computing and Applications Journal, Springer-Verlag 2
2-3 93-110
S. Achchab. Singular perturbation of single species model with time-delay 2008 International Journal of
Mathematics and Statistics (IJMS’2008) 2 2 18-29
2007
H. Panetto, S. Baïna, G. Morel. Mapping the IEC 62264 models onto the Zachman framework for analysing
products information traceability: a case study 2007 Journal of Intelligent Manufacturing (JIM’2007).
M. Berrada, B. Bounabat. Modelling and Simulation of Multi-Agent Reactive Decisional Systems using
Business Process Management Concepts, March 2007. International Review on Computers and Software
(IRECOS’2007)
2006
K. Baïna, K. Benali et C. Godart. DISCOBOLE: A service Architecture for Interconnecting Workflow
Processes. 2006 Computers In Industry’2006, Journal - Special issue on Collaborative Environments for
Concurrent Engineering.
2005
A. Aarooud, B. Bounabat. Modelling the Handover function of Global System for Mobile Communication
2005 The International Journal of Modelling and Simulation (IJMS’2005)- ACTA Press
B. Achchab et S. Achchab. Some Remarks about the Hierarchical A Posteriorie Error Estimate 2005
Journal of Numerical Methods for Partial Differential Equations (JNMPDE’2005) 20 6 114-135

37. www.ensias.ma www.um5s.ac.ma
Karim Baïna’s
research

38. Karim’s Baïna research within
Alqualsadi 5 axes
Axe 1 : EA Gouvernance Axe 2 : EA Integration Axe 3 : EA Quality
IT Balanced scorecards applied BPM, SOA/Semantic SOA, Process model pre&post
to BPI, BAM/SAM & IT Alignment Service ontology evolution, execution validation &
Mobile social netwoks reconfiguration
Enterprise Architecture
Axe 5 : Applied Maths Methods for EA Axe 4 : EA Applied to ICT4D
Graph reduction algorithms for business process Service ontology change
structural conflict detection management for life sciences

39. Karim’s Baïna participation in
design, management, and
development of research
prototypes, ENSIAS ©
WorkflowChecker WorkflowMiner
WFMS portfolio management
WorkflowSelector
BPM PDCA loop

40. WorkflowMiner, ENSIAS-LORIA©
WfMS Workflow Logs
3. W
ork
flo
w Min
Workflow in action ing
Enterprise
1.
Process
W
A0 A1 A2 A3
or
2. Workflow Execution
kf
Mined Workflow Model
lo
w
ign
-Des
D
re
es
ork flow
ig
4. W
n
A0 A1 A2 A3
A4
Designed Workflow Model

41. WorkflowMiner, ENSIAS-LORIA ©
Papers Impact : ENSIAS R&D
prototyping,
published in DEXA’2005, CAiSE’2006,
and SOCA’2008 are referenced beside
key reference BPM papers in the
domain.
- since 2004, more than 30 ENSIAS engineers have worked on WorkflowMiner
- more than 1000 person days of work during three years
Walid Gaaloul, Karim Baïna, and Claude Godart. "Workflow Mining : discovery of workflow patterns by
execution log analysis" in French "Fouille de workflow, Découverte de patrons de workflows par
l’analyse des traces d’exécution", Revue Technique et Sciences Informatiques(TSI’2010) French
reference journal, Hermès-Lavoisier.
Walid Gaaloul, Karim Baïna, and Claude Godart. Log-based Mining Techniques Applied to Web
Service Composition Reengineering. Service Oriented Computing and Applications Journal (SOCA'08),
2(2-3):93-110, July 2008. Springer-Verlag
K. Baïna, W. Gaaloul, R. El Khattabi et A. Mouhou. WorkflowMiner : a New Workflow Patterns and
Performance Analysis tool. (CAiSE’06) Forum, Luxembourg, Grand-Duchy of Luxembourg, June 5-9,
2006.
W. Gaaloul, K. Baïna et C. Godart. Towards Mining StructuralWorkflow Patterns. (DEXA’05), volume
3588, pages 24–33, Copenhagen, Denmark, August 22-26 2005. Springer-Verlag.

43. WorkflowChecker, ENSIAS ©
Papers Impact : ENSIAS R&D prototyping, published in ICEIS’2008 and then in CoopIS’2008 begins to be
referenced within some BPM research work with two well known universities, and journal papers. The
papers bring an improvement of first graph reduction algorithms for structural verification of processes,
and this improvement is referenced beside key reference papers in the domain.
Step by step graph reduction based business process
structural verification algorithm
within WorkflowChecker
-since 2007, more than 15 ENSIAS engineers have
worked on developing WorkflowChecker during three years
- more than 600 person days of design & development work
Fodé Touré, Karim Baïna, and Walid Gaaloul. Toward a hybrid algorithm for workflow graph
structural verification. In Proceedings of the 10th International Conference on Enterprise Information
Systems (ICEIS'08), Barcelona, Spain, June 12-16, 2008.
Fodé Touré, Karim Baïna, and Khalid Benali. An efficient algorithm for workflow graph structural
verification. In Proceedings of the 16th International Conference on Cooperative Information Systems
(CoopIS'08) Monterrey, Mexico, Nov 12 - 14, 2008, Lecture Notes in Computer Science. Springer-
Verlag.

44. WorkflowChecker /
WorkflowMiner, ENSIAS ©
http://workflowminer.drivehq.com/workflowchecker.avi
http://workflowminer.drivehq.com/workflowminer.avi

45. WFESelector ENSIAS ©
Papers Impact : ENSIAS R&D prototyping, and case study results, published in RCIS’2007 and then in
ICEIS’2007 could influence and drive a huge BPM research community (many researchers in many well
known universities, and many international conference & journal papers) : (i) to be more attracted by
BPM open source benchmarking within a such large open source community, and (ii) to focus later on
(instead of being lost within a such fertile production) only on the top 3 WFE : jBPM, OpenWFE &
Enhydra Shark with newer visions, and interests both profitable for BPM open source community and
BPM research.
Screen shot of one execution WFESelector
applied on studied open source
workflow engines evaluation case study
TOP 3
TOP 8 TOP 6
K. Baïna ©
ICEIS’2007
- study has been achieved in June 2006, and than validated in 2007 newer open source versions
- the WFESelector tool has been built on April 2007.
-35 criteria synthetised into 2 dimensions
- more than 100 ENSIAS engineers worked on more than 40 open source tools during two years
-more than 3000 person days of design, evaluation, and development work
Karim Baïna, Fatima-Zahra Azayite, Nabil Belakbir, Hicham Srir, and K. Benali, Workflow Engines
Comparison Model. Proceedings of the 1st Research Challenges in Information Science (RCIS’2007), April 23-
26, Ouarzazate, Morocco.
Karim Baïna "WFEselector - a tool for comparing and selecting workflow engines". In Jorge Cardoso, José
Cordeiro, and Joaquim Filipe, editors, Proceedings of the 9th International Conference on Enterprise Information
Systems (ICEIS‘2007) (1), Volume DISI, Funchal, Madeira, Portugal, June 12-16, 2007, pages 330-337.

46. French BPM book,
on sale since May 2009
Business processes,
concepts, models, and systems

47. History and Cultural
parenthesis
King Rollon, King Roger II, Al-idrissi, Dreses (latin) Al-kalsadi (aka alqualsadi)
860 – 930 1095 – 1154 1110 – 1165 1412 – 1486
King of Vikings King of Sicily Geographer, Mathematician
Descendant of King Rollon
Sponsor of Al-idrissi
and Botanist

48. Kingdom of Morocco – History,
Religion, and Culture
Multi Pot of rich cultural and genetic patrimonies
Pre-islamic period : Africans, Berbers, Phoenicians, Romans,
Carthaginians, Vandals, Byzantines, Wisigoths
Islamic period : Arabs (7 islamic kingdom dynasties), Andalus
Recon-quest period : Castilians (Portuguese, Spanish)
French period : Marsh, 30th 1912, French Protectorate (Tangier was
international: Spain/England/ France/Morocco)
3 religions : Judaism (since pre-islamic period among locals and ancient
migrants), Islam, Catholic religion (european citizens or residents)
Roman church was active in pre-islamic period (Saint Augustan was a
romanised berber !!)
Many berbers, and romanised berbers, pre-islamic kingdom dynasties,
and tribes
7 islamic (arabs and berbers) kingdom dynasties : Idrissids, Almoravids,
Almohads, Marinids, Wattasids, Saadis, Alaouites
The origin of Morocco country name is coming from Berber name
Marrakech

49. Kingdom of Morocco – current State,
Economy, Demography, Statistics
1631 begining of the line of Alaouite Kingdom dynasty
Moroccan Nov 16th, 1956 independence
Mohammed VI King of Morocco since 1999 (23th, of alaouite
dynasty)
~31M inhabitants
2010 GDP 5.10, GDP real real growth rate %23
More than 11.000.000 internet user (35%), More than 650.000
inhouse internet connection (>12%)
50 multinational company have been recently attracted by
moroccan offshoring initiatives
700 subsidiaries of french companies employing 100 000 active
person
10 000 engineers national Program (current yearly graduated
engineers × 2.5)
30 000 entreprises creation till 2013 ( « Emergence & envol »,
Digital Morocco 2009-2013 Plans)
Morocco advanced status toward EU
Tangier Med (Mediterranean Mega-Port)

50. Swedish - Moroccan Kingdoms
medieval historical key events
429 Vandals migrations
554-567 Wisigoths reach northen Morocco (* western Goths
(Tervinges) were separated from Ostrogoths (eastern Goths) since 257)
710 beginning of Islamic conquest of christian Wisigoths kingdom
711 Wisigoth coalition with Arabs againt their Wisigoth king Rodrig
718 - 1492 Normand/Castillans/Aragons reconquest of christian
Wisigoths kingdom
844, first Al-Ghazal Cordovan embassy mission to Danish/Irish
Vikings to stop helping Castillans
1154, Roger II, Norman king of Sicily (descendant of Rollon, king of the Viking)
ordered and sponsored Al-idrissi 1110-1165 Geographer for writing
first European and Western Geography Atlas (“Kitab nuzhat al-mushtaq fi
ikhtiraq al-afaq”) litterarly (“The Book of the Pleasing Excursion of One
who is Eager to Explore the Horizons”) aka (“Kitâb Rudjâr” ) (The Book
of Roger) Tabula Rogeriana
and since this time swedish-moroccan scientific
cooperation is being continuing;-)

51. Who was Alqualsadi ?
First name : Abou Al Hassan ibn Ali ibn Muhammad
Surname : al-Qalasadi a.k.a. : Al-Qalsadi, Al-Qalasadi, Al-Kalsadi
birth : on 1412, Bastah, (north of Granada) AlAndalous (current Andalusia)
death : on 1486, Béja, Ifriqiya (current Tunisia)
expertise : Arithmetics, Algebra, Astronomy
contribution
Transforming language (numbers values, operations, & relations) to meta-language (symbolic
arithmetic variables with symbolic operations and relations in arabic alphabet lexicon)
Abreviation of Variable Names to Symbols (long equations algorithms become shorter & easier)
unknown X is born : ‫ ش‬is the abbreviation of shay that will be translated in italian later as « causa » and then will be abreviated
to X
Abstraction and symbolisation of arithmetic operations
examples
3 9 means √ 9 = 3
Lexical meta-language
36 ‫ 6 م ل‬means 62 = 36
27 ‫ 3 ك ل‬means 33 = 27
becomes = latin alphabet
126 ‫ 6 م و 3 ك ف 2 ل‬means (62 + 33) × 2 = 126
‫ ش ج ش‬means (√x) 2 = x
application to formalisation and resolution of algorithms of algebric (polynomial, diophantine)
equations
some of his arithmetic vulgarisation books
« Raising the veil of the science of the letters’ dust » (kashf alasrar aan ilmi hurufi alghubar)(alghubar means
« dust » and here stands for written arithmetic with numerals.
« Clarification of the science of arithmetic »(al-tabsira fi‘ilm al-hisab)
well known for his pedagogical approach
no prerequisites assumption is done (to be able to target beginner level), clear and direct style,
avoiding complex demonstrations, exposing only practical methods, style clair et direct, a huge
number of exercises, many illustrations of arithmetic algorithm rules

52. Who was Alqualsadi ?
is the origin of, among others, visual symbolic
representation of the square root (‫ )ج ذ ر‬Alqualsadi
abreviated to (‫ )ج‬so it gives :
9 9 9
becomes becomes
Please notice visual similarities !
see. Solomon Gandz, On the Origin of the Term "Root", The American Mathematical Monthly,
Vol. 35, No. 2 (Feb., 1928), Mathematical Association of America

53. Example of Alqualsadi symbolic abreviations
in algebra Applications : Pythagorean
Algebric Proof
Concrete Language Abstract Meta-Language
(A+B)2 = A2 + 2*(A*B) + B2
Algebric proof of the
Pythagorean theorem,
by symbolic quadratic equations
Geometric proof of the
Pythagorean theorem, (A+B)2 = C2 + 2*(A*B)
by Pythagoras
A2 + 2*(A*B) + B2 = C2 + 2*(A*B)
Thus: A2 + B2 = C2 q.e.d.

54. Open discussion

55. Aknowledgments
Alqualsadi EA research team
would like to thank
all MENA project sponsors and actors
and to thank you for your
presence, attention, and questions
www.ensias.ma www.um5s.ac.ma